(19)

(11)

EP 1 718 993 A1

(12)

(43) Date of publication: 08.11.2006 Bulletin 2006/45 (21) Application number: 05708277.8 (22) Date of filing: 10.02.2005

(51) International Patent Classification (IPC):  G01V 1/20(2006.01) G01H 9/00(2006.01) (86) International application number: PCT/GB2005/000452 (87) International publication number: WO 2005/078479 (25.08.2005 Gazette 2005/34)

(84) Designated Contracting States: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU MC NL PL PT RO SE SI SK TR (30) Priority: 10.02.2004 GB 0402914 (71) Applicant: Statoil ASA 4035 Stavanger (NO)	(72) Inventors: MELDAHL, Paul N-4033 Forus (NO) VIKHAGEN, Eiolf N-7045 Trondheim (NO) LOKBERG, Ole, Johan N-7048 Trondheim (NO) (74) Representative: Rees, David Christopher  Kilburn & Strode 20 Red Lion Street London WC1R 4PJ London WC1R 4PJ (GB)